"Simon [Cowell] and his team and Britney and her team have had long discussions and everything has been done to give it the best possible chance," Clifford said.

"Simon's totally aware of her background, and everyone's as confident as they can be that it's the right time and place for Britney.

"Those close to her are 100% confident that this will succeed."

Spears's friend and backing singer Melissa Lifton added to the magazine: "Britney feels like this signifies a whole new chapter for her, and she's really honored and a bit nervous that she gets to judge who has talent or not.

"But what she really sees The X Factor as is a chance to redeem herself. She's excited to show the world that she's funny, charming, genuine and not crazy."